Absorption pefrigeration systems



March 15, 1955 A. A. BERESTNEFF ABSORPTION REFRIGERATION SYSTEMS Original Filed July 13, 1946 2 Shets-Sheet l O o o o 0 0 0 INVENTOR.

0 0 M O 0 0 O O March 15, 1955 A. A. BERESTNEFF 2,703,968 4 ABSORPTION REFRIGERATION SYSTEMS Original Filed July 15, 1946 2 Sheets-Sheet 2 INVENTOR. A M .BY

United States Patent 2,703,968 ABSORPTION REFRIGERATION SYSTEMS Alexis A. Berestnelf, Syracuse, N. Y., assignor to Carrier Corporation, Syracuse, N. Y., a corporation of Delaware Original application July 13, 1946, Serial No. 683,387. Divided and this application August 3, 1951, Serial No. 240,230

2 Claims. (Cl. 62-119) This application is a division of my co-pending application, Serial No. 683,387, filedIuly 13, 1946, now Patent No. 2,565,943, entitled Absorption Refrigeration Systems, and relates to an absorption refrigeration system including an improved arrangement for sealing purge connections to the absorber.

The chief object of the present invention is to provide an absorption refrigeration system including purging mechanism connected to the absorber, and improved mechanism for sealing the connection between the purging means and the absorber.

A further object is to provide improved sealing mechanism for the connection between the purge and absorber of an absorption refrigeration system. Other objects of the invention will be readily perceived from the following description.

This invention relates to an absorption refrigeration system comprising in combination a shell having end Walls, a plurality of tubes through which cooling water is passed disposed in the shell and cooperating therewith to form an absorber, a water header at an end of said shell adapted to supply cooling water to said tubes, the wall of said header having an opening therein, a purge pipe extending through the opening in the wall of said water header and a wall of said shell adapted to withdraw non-condensible gases from said absorber, and means for sealing the connection between the purge pipe and said header, said means including a thread formed in the wall surrounding the header opening, packing means disposed in said opening and means adapted to cooperate with said thread to compress said packing means thereby rendering the opening secure against leakage.

The attached drawings illustrate a preferred embodiment of my invention in which Figure 1 is a diagrammatic view illustrating the flow of solution through the various elements of the absorption refrigeration system;

Figure 2 is a view in elevation illustrating the manner in which the purge pipe is supported in the absorber; and

Figure 3 is a sectional view showing the means by which a secure joint is formed between the purge pipe and the absorber and header.

Referring to the drawings, there are shown horizontally extending drums or shells 4 and 5, shell 5' preferably being secured in place above shell 4. Shell 4 encloses a longitudinally extending absorber arrangement 6 and a longitudinally extending evaporator arrangement 7 placed above the absorber 6. Chilled water treated by the system is circulated by a pump 8 through an air conditioning device of any desired type (not shown) and is returned from the air conditioning device to the evaporator 7 through line 9. The chilled water is sprayed in evaporator 7 by a suitable spray arrangement 10, the chilled Water being flash-cooled in the evaporator and being drawn from the evaporator through line 11 by pump 8 and again forwarded to the air conditioning device.

Shell 5 encloses a longitudinally extending generator arrangement 12 and a longitudinally extending condenser arrangement 13 placed above the generator 12. Weak solution is withdrawn from absorber 6 by pump 14 through line 15 and is forwarded to the generator 12 through lines 16, 17, heat exchanger 18 and line 19. A restriction 101 may be placed in line 17. Strong solution is withdrawn from generator 12 through line 20,

See

overflow arrangement 21, line 22, heat exchanger 18 and line 23 to an ejector 24 which forwards strong solution through line 25 to the absorber 6. The strong and weak solutions are placed in heat exchange relation in exchanger 18.

The term weak solution is used herein to define a solution containing a large amount of refrigerant so that the solution is weak in absorbing properties. The term strong solution defines a solution which is relatively deficient in refrigerant and, consequently, a solution which possesses enhanced properties of refrigerant absorption.

Various combinations of refrigerant and absorber may be used in the present system. A solution consisting of lithium bromide and water is highly satisfactory. Other salt solutions may be used as desired; when the system is operated at high temperatures (above freezing temperature) a solution of lithium chloride and water or a solution of sodium hydroxide and water, for example, may be used.

A pump 26 passes cooling water through line 27 to the coil of absorber 6 and then forwards the water through line 28 after passage through absorber 6 to the coil of condenser 13. After passage through the coil of condenser 13 the water is discharged or, if desired, may be re-used as in the case of a cooling tower.

A line 29 is adapted to withdraw vapor condensate from condenser 13, the vapor condensate passing through a pro-cooler assembly 30 and then being returned through line 31 to evaporator 7 A suitable purge arrangement 32 is provided to purge condenser 13 and absorber 6 of air or other non-condensible gases. Purge 32 may operate intermittently or continuously, as desired.

It is desirable that the capacity be changed immediately upon change in load to attain most satisfactory operation. The temperature of the chilled water may be used to indicate a change in load, since a decrease in the temperature thereof from a predetermined point indicates that the load imposed upon the system has decreased.

As the temperature of the chilled water leaving the evaporator decreases the capacity of the system may be decreased accordingly by throttling the volume of strong solution passing to the absorber 6. 1

For this purpose a valve 57 is placed in line 16 between ejector 24 and pump 14 at a point between pump 14 and the juncture of line 17 with line 16. Valve 57 is actuated by a control 58 operated by a bulb 59 placed in or adjacent line 11. As the temperature of chilled water passing through line 11 decreases, fluid in bulb 59 contracts, and control 58, in accordance therewith, tends to move valve 57 toward a closed position, thereby decreasing the amount of weak solution being forwarded to generator 12 through lines 17 and 19 proportionately to the decrease in the temperature of the chilled water. Movement of valve 57 toward a closed position also decreases proportionately the amount of weak solution passing to ejector 24 thereby reducing the velocity of such solution to the nozzle of the ejector and, consequently,- a smaller quantity of strong solution is entrained or induced from line 23. The capacity of absorber 6 is controlled by the decreased wetting action provided by the reduction in total solution and by the reduction in strong solution therein, in accordance with the load imposed on the system.

Valve 60 in steam line 51 controls the amount of steam passing into the tubes of generator 12 in accordance with the load imposed upon the system. Valve 60 is actuated by control 61 operated, in turn, by a bulb 62 placed in or adjacent line 20.

The amount of condensing water passing through condenser 13 is controlled by means of a valve 63 placed in line 28' actuated by a thermostat control 64 operated by means of a bulb 65 placed in or adjacent vapor condensate line 29.

While generally it is desirable to maintain the concentration of the solution constant in accordance with temperature and pressure conditions in shell 5 in some cases it may be desirable to decrease the concentration of the solution at partial load. For this purpose a suitable reset control is provided to change the control point of control 61. Control 61 may be regulated by air pressure through line 66" connected to the air line which operates valve 57. As air pressure in line 66" decreases it re-sets the control point of control 61 in accordance with the desired temperature of the solution leaving the generator and pressure in shell 5, thereby indirectly de-.

creasing the concentration of the solution to the desired degree.

Purge pipe 72 extends longitudinally of absorber 6 and has openings therein to suck in air and other noncondensible gases collecting in absorber 6. Pipe 72 is connected by line 73 to purge arrangement 32. Valve 73' is placed in line 73 to permit it to be closed when desired.

In Figures 2 and 3 there is illustrated the manner in which purge pipe 72 is placed in absorber 6 and is secured in place therein to prevent leakage from the absorber to the ambient atmosphere. Purge pipe 72 extends ngitudinally of absorber 6 and is supported at one end of the absorber by means of a cradle 95 welded to shell 4. The end of pipe 72 rests on cradle 95 and is supported thereby, but it is not attached to the cradle. At the opposite end purge pipe 72 passes through the wall 96 of shell 4 and through wall 97 of water header 98. An opening is formed in wall 96 and is threaded to receive a bushing 99 Welded to tube 72. When assembling the purge pipe in the structure the bushing is coated with a suitable sealing composition and is screwed into the threaded opening in wall 96, thus serving to close and to seal the opening between the absorber and header 98. An opening is formed in wall 97 of header 98 through which purge pipe 72 passes. wall of such opening is threaded to receive a gland 100. A packing ring 102 is placed about pipe 72 within such opening and is compressed in place by means of gland 100, thus securely sealing the opening between the header and the ambient atmosphere to prevent leakage of water during operation of the machine.

The present invention provides an absorption refrigeration system including mechanism for purging the absorber in which the purge pipe placed in the absorber is securely sealed to prevent leakage between the water header and the ambient atmosphere as well as leakage between the absorber and the water header. The means At least a portion of the so provided are inexpensive and easily and readily placed in position to support and seal the purge line. The arrangement of the absorber concentrates non-condensible gases at the bottom of the absorber so that such non-condensible gases can be removed easily from the system through the purge arrangement.

While I have described a preferred embodiment of my invention, it will be understood the invention is not limited thereto, since it may be otherwise embodied within the scope of the following claims.

I claim:

1. In an absorption refrigeration system, the combination of a shell having end walls, a plurality of tubes through which cooling water is passed disposed in the shell and cooperating therewith to form an absorber, a water header at an end of said shell adapted to supply cooling water to said tubes, the wall of said header having an opening therein, a purge pipe extending through the opening in the wall of said water header and a wall of said shell adapted to withdraw non-condensible gases from said absorber, and means for sealing the connection between the purge pipe and said header, said means including a thread formed in the wall surrounding the header opening, packing means disposed in said opening and means adapted to cooperate with said thread to compress said packing means thereby rendering the opening secure against leakage.

2. A system according to claim 1, in which a threaded opening is provided in the shell Wall, a bushing secured to said pipe cooperates with said thread to hold the pipe in position, a shoulder is provided in the header opening against which the packing means rests and a gland is provided to compress the packing means against said shoulder to seal the opening against leakage.

References Cited in the file of this patent UNITED STATES PATENTS 143,314 Archbold Sept. 30, 1873 502,402 Kaye Aug. 1, 1893 1,404,299 Joyner Jan. 24, 1922 2,374,564 Reid Apr. 24, 1945 2,470,756 Berestnefi May 24, 1949 2,473,384 McNeely June 14, 1949 2,565,943 Berestnelf Aug. 28, 1951 

